Cataracts - A colony of miniature German Schnauzer dogs with genetic cataracts has been established. The cataract has been classified clinically and studies are presently being undertaken concerning the histochemical and histopathologic changes in the lens. Sickle cell retinopathy - Studies in erythrocyte sickling in susceptible animals has been performed in order to document changes produced at the retinal level. In vivo sickling experiments were conducted on Japanese Sika deer. Data were collected to evaluate changes in serum chemistry, blood gases, erythrocyte morphology and retinal blood flow. Histopathologic sections, as well as flat retinal mounts of all eyes of all animals were obtained. Manuscripts for the procedure of sickling as well as the ophthalmic result have been submitted for publication. Heredomacular degeneration in baboons. Behavioral, electrophysical and histopathologic studies have been performed on a baboon with retinal degeneration. Several other related baboons with minimal macular lesion are presently being followed. Behavioral abnormalities are presently being correlated with changes seen on fundus photography, fluorescein angiography and electroretinography.